Lawn mower



P. A. CAMPBELL'.

LAWN MOWER. APPLICATION FILED JUNE4. 1921.

11,423,999, PatenteaJu1y25,1922.

f rios- UNIT.,

LAWN MowEE.

i Application filed June 24,

`T all .whom t may concern Beit known that I, PHILIP .ALEXANDER CAMEEELL, a subject ofthe King of Great Britain, and a vresident ,of the city of Vanncouver, in the Province of British Columfbla, Canada, have invented certain new and .useful yImprovements In Lawn" Mowers, of

; .which .the following is a specification.

My invention relates ytoimprovements in `lawn mowers, and the object of my invenition 1s to devise a mower in which the cut- Ating `blades operate laterally in-'sheardike fashion so that the grass is shear cutv as opposed .to the rotary method ofcutting and @is :therefore out more closely, evenly, andr Icleanly, .thus maintaining its greenness and vigor. A further object is to provide a mower in which strain on the parts during operation is reduced to the minimum and ithus the .life of the machine is lengthened and replacement ofnew parts due to wear and Ytear is seldomrequired. v f

I vattain `these objects by the construction illustrated in the accompanying drawings Fig. 1 is a side view of the, mower, the near side main wheel being removed.

Fig. 2 isa-plan view.

Fig. 3 is a fragmentary sectional view taken through line 3 3 of Fig. 2.

Fig. 4 is a fragmentarysectional view taken through the line 4-4 of Fig. 2.

Fig. 5 is a fragmentary sectional view taken through the line 5-5 of Fig. 2.

Similar figures of reference indicate similar parts throughout the several views.

1 indicates a horizontal plate having a slot 2 in its front edge which plate is secured transversely to the forked lower ends 3 and 4 of the frame 5 of the mower, the upper end of the frame being inclined upwardly at the proper angle for positioning correctly the operating handle 6, which is of the usual type, being seated at its lower end in a socket 7 formed on the frame while at its upper end itis provided with the cross-bar 8.

Slidably. mounted for lateral movement in the slot 2 is a lower knife-carrying bar 9 to which is secured a plurality of spaced knives 10 similar to those found in moving sickles, that is, substantially flat triangular shaped blades, the opposite converging edges of which are sharpened, while slidably mounted on top of the plate 1 for Specification of Letters Patent;

lateralmovement thereon and infsliding con- .tact with the lower bar 9 is an upperknifecarrying bar 1'1 also having secured to it a pluralityof knives 12, and the front part of each forked end 3 and 4 is cutaway, as shownat 13 inFigs. 4 andi), so that a slot is'formed-.betwee'n the forked end rand the plate 1 inwhich, the upper bar is-slidably movable. Each forked end 3 and 4.is provided witha slot 14`and 15 respectively through which extend pins 16 and 17, pin 17 being secured vertically tothe upperbar 11,

as-shown in Fig.-y 5while pin 16v is secured vertically to the lower bar 9 and extends upwardly ythrough-slots 18 and 19 .formed in the plafteil andl thelupper bar 11corresponding to the slot14, andfthese slots areof'suficient length to-.permit full ltravel lof the pinstherein as the knife bars are moved during the "operation of the machine.V The upper knife bar '11 is further provided with a slot 2O at midlength in which is laterally reciprocable a vertical pin secured into the upper knife -bar 11.

A22 and 23 indicate bearings formed on op-` :posite sides ofthe frame 5 inwhich is Yrotatablyf mounted a shaft-,24 which extends through/the lbearings and is provided von its opposite ends with the main wheels 25 and 26 on which the machine is movable, these wheels being formed with internal gears 27 and 28, and meshing with these gears are smaller pinions 29 and 30 secured respectively to the outer ends of shafts 31 and 32 rotatablymounted in bearings 33-34 and 35-36 formed on the frame, as shown in Figs. 1 and 2. Secured tothe shafts 31 and 32 to rotate between the respective bearings are sheaves 37 and 38 the` peripheries of which are grooved, as at 39, and these sheaves are offset at anangle, with relation to their horizontal or shafts axis, so that when rotated their front edges will move laterally to opposite sides of their other horizontal axis, or in other words, the front edges of the sheaves when rotated will make two lateral strokes, inwards and` outwards respectively, with each revolution of the sheave, the length of each stroke being equal to the amount of offset, and the sheaves are arranged so that their front edges are ofset away from each other, as shown in Fig.I 2, when at the end of the outstroke.

40 and 41 indicate levers mounted on the forked ends 3 and 4 respectively and fulcrumed on screws 42 and 43 secured into' moving it forward the sheaves 37 and 38 are.

rotated, -makingthe strokes already described so that the levers 40 and 4l are swung r on their fulcrums 42 and 43,' causing the front ends of the levers to move to and from each other, and as these ends are connected to the pins 1G and17 -which are in turn secured to the respective upper and lower knife blades, vvthe blades are consequently V-moved to and fro inopposite directions over each other so that the knives cut the f' v[other fork slot, a pair of sheaves rotatably vmounted on opposite sides of the frame each hoffset so that its forward edge moves latergrass between them inthesame manner as shears.

From the foregoing 1t will be seen that I have devised a lawn mower which is highly practical and of great service.

What I claim as my invention is 1. A lawn mower 'comprising a wheeled frame forked at its lower front endand provided in each .forked arm with a transverse slot, a transverse plate secured to the forks of the framehaving a slot in its front edge and a slot registering with one of the fork slots, alower knifed bar having its rear edge slidably mounted in said front edge slot, an upper knifed bar superposed on said plate having a slot resistering with the fork and rotated, a pairy of levers each fulcrumed intermediate its length on opposite sides of plate slots aforesaid, a vertical pin secured to said lower knifed bar projecting through 40 the upper knife slot, the plate slot, and the fork slot, a vertical pin secured to the upper knifed bar projecting through the other fork slot, and means for simultaneously imparting opposite reciprocating motion to said pins.

Y y2. A lawn mower comprising a wheeled frame forked at its lower front, end provided in each forked arm with a'transverse slot, a transverse plate secured to the forks of the frame having a slot in its front edge and a slot registering with one of the fork slots, a lower knifed bar having its rear edge slidably' mounted in said front edge slot, an upper knifed ibar superposed on "said plate having a slot registering with the fork and plate slots aforesaid, a vertical pin secured to said lower knifed bar projecting through .the other fork slot, a vertical vpin secured to the upper knifed bar projecting through the ally inwardly and outwardly as the sheave is the frame, the outer ends of said levers being connected respectively to the upper knife bar pin and the lower knife bar pin, their inner ends being in engagement respef/ tively with said sheaves, and means for ro-` tating said sheaves.

Dated at Vancouver, B. C., this 9th day of June, 1921.

PHILIP ALEXANDER CAMPBELL. 

